Obama To Honor Boston Bombing Victims

President Barack Obama gestures as he speaks during a news conference in the Rose Garden of the White House, in Washington, on Wednesday. (AP Photo)

President Barack Obama sought to soothe a nervous nation
Thursday and draw attention to those killed and gravely wounded in what he
called an "act of terror" at the Boston Marathon.

Americans also looked to the president to offer reassurances
about the nation's safety as investigators scrambled to answer key questions
about an attack with origins that were yet unknown.

The president was to speak at an interfaith service in
Boston honoring the three people killed and 170 injured when a pair of bombs
ripped through the crowd gathered Monday afternoon near the finish line of the
famous race.

Investigators say they had an image of a potential suspect, though much
about what happened remained a mystery, keeping tensions high in Boston and
elsewhere around the country.

Compounding the nation's jitters were letters sent to
Washington officials that contained suspicious substances, including ones
addressed to Obama and to Sen. Roger Wicker, R-Miss., that showed traces of
poisonous ricin in initial tests. The letters evoked eerie parallels to the
anthrax attacks that followed the terrorist attacks of September 11, 2001.

It was against that backdrop that Obama and his wife,
Michelle, arrived in Boston Thursday morning, joining a crowd at the Cathedral
of the Holy Cross for a "Healing Our City" service. The Obamas sat at
the front of the church next to Massachusetts Governor Deval Patrick as the service
began.

White House spokesman Josh Earnest told reporters traveling
with the president on Air Force One that Obama also planned to meet with some
of those injured, as well as with the first responders who rushed toward the
blast to help the scores of runners and spectators.

Earnest said Obama received a briefing from national
security adviser Lisa Monaco on the status of the investigation into the Boston
blast before departing the White House. Accompanying Obama aboard Air Force One
were members of the Massachusetts congressional delegation, including Sens.
Elizabeth Warren and Mo Cowan.

"We send our support and encouragement to people who
never expected that they'd need it - the wounded civilians who are just
beginning what will be, I'm sure for some of them, a long road to recovery,"
Obama said Wednesday in a likely preview of his remarks at the service.

The president has stepped into this role as the nation's
consoler-in-chief many times before in his presidency, most recently in
December after the massacre of 20 first-graders and six educators at an
elementary school in Newtown, Conn. Before that, there were the deadly
shootings in Aurora, Colorado, Tucson, Ariziona, and Fort Hood, Texas, as well as the
natural disasters that tore apart towns and neighborhoods in Missouri and the
New York-New Jersey area.

This time, Obama must confront the unique challenges of a
terror attack that inevitably revived memories of 9/11.

As he did in a
statement from the White House on Tuesday, the president was expected to urge
the public to remain vigilant, while declaring that "the American people
refuse to be terrorized."